Issues with test execution using projects & tags

Hello 👋 I've been working to implement a new release strategy using projects & tags but am hitting issues. The way I have it setup currently is this, 2 projects each containing their own @E2E tag. I'm using npm scripts in package.json to run them, locally & in remote envs. As part of creating the projects I moved some tests into their own folder structure (& told playwright project config where to look). I also created new spec.ts files & removed the tests I no longer needed in each - they were just duplicate tests with different tags. These projects run fine when I use the --projects flag in package.json but if I simply try grepping the first part of the e2e tag, @E2E- for e.g it throws errors. The errors are test code related as if something isn't implemented properly. I've gone over my changes & don't believe I've made any changes that would result in this. So the only conclusion I can make is that my implementation of projects\tags isn't correct. So, my question is.. if you start using projects in an existing suite, is there anything else you need to do or consider when you config them? And am I correct in my expectation that you can grep for tags across projects? Thanks in advance!